Modifier, usage therefor, production method for modifier, and carrier for additive material

ABSTRACT

Disclosed herein are a modifier having a continuous phase (A) containing a second polyolefin resin and a dispersed phase (B) containing a polyamide resin and a modified elastomer, wherein the dispersed phase (B) is composed of a melt-kneaded product of the polyamide resin and the modified elastomer having a reactive group, and wherein when a total of the continuous phase (A) and the dispersed phase (B) is 100% by mass, a content of the dispersed phase (B) is 80% by mass or less, a method for using the modifier, including mixing 0.5 parts by mass or more but 70 parts by mass or less of the modifier per 100 parts by mass of a first polyolefin resin, and a method for producing the modifier, including the step of melt-kneading the second polyolefin resin and a melt-kneaded product of the polyamide resin and the modified elastomer.

TECHNICAL FIELD

The present invention relates to a modifier and a method for using thesame, a method for producing the modifier, and a carrier for additives.More specifically, the present invention relates to a modifier that canbe added to a polyolefin resin to obtain a molded body having improvedimpact resistance and a method for using the same, a method forproducing the modifier, and a carrier for additives.

BACKGROUND ART

Heretofore, attempts have been made to mix different types of resins toobtain mixed resins that can offer characteristics superior to thosethat are offered by each of the resins alone. For example, a techniqueis disclosed by the present inventors in the following PatentLiteratures 1 to 4, in which a polyamide resin and a polyolefin resinare used in combination to obtain a mixed resin having improvedcharacteristics.

CITATIONS LIST Patent Literatures

Patent Literature 1: JP 2013-147645 A

Patent Literature 2: JP 2013-147646 A

Patent Literature 3: JP 2013-147647 A

Patent Literature 4: JP 2013-147648 A

SUMMARY OF INVENTION Technical Problems

Patent Literature 1 discloses a polymer alloy of a polyamide resin and apolyolefin resin (thermoplastic resin composition) obtained by using, asa compatibilizer, a modified elastomer having a reactive group capableof reacting with the polyamide resin.

Patent Literature 2 discloses that a plant-derived polyamide resin canbe used as a polyamide resin contained in a polymer alloy of a polyamideresin and a polyolefin resin.

Patent Literature 3 discloses a polymer alloy containing a polyamideresin and a polyolefin resin, which has a resin phase-separatedstructure having a continuous phase, a dispersed phase dispersed in thecontinuous phase, and a fine dispersed phase further dispersed in thedispersed phase.

Patent Literature 4 discloses that a polymer alloy excellent in impactresistance can be obtained by first melt-mixing a polyamide resin and acompatibilizer and then further melt-mixing the obtained mixed resin anda polyolefin resin.

However, according to the above Patent Literatures 1 to 4, the presentinventors have studied the production and use of these polymer alloysalone, but have not studied the use of these polymer alloys togetherwith other resins.

In light of the above circumstances, it is an object of the presentinvention to provide a modifier that contains a polyamide resin and apolyolefin resin and that can be blended with a polyolefin resin toobtain a molded body having excellent impact resistance and a method forusing the same and a method for producing the modifier.

Solutions to Problems

The present invention is as follows.

The present invention is directed to a modifier that can be added to afirst polyolefin resin to obtain a molded body having improved impactresistance, the modifier including:

a continuous phase (A) containing a second polyolefin resin; and adispersed phase (B) dispersed in the continuous phase (A) and containinga polyamide resin and a modified elastomer, wherein

the dispersed phase (B) is composed of a melt-kneaded product of thepolyamide resin and the modified elastomer having a reactive group thatreacts with the polyamide resin, and wherein

when a total of the continuous phase (A) and the dispersed phase (B) is100% by mass, a content of the dispersed phase (B) is 80% by mass orless.

A modifier according to claim 2 is the modifier according to claim 1,wherein the modified elastomer is an olefin-based thermoplasticelastomer having, as its skeleton, a copolymer of ethylene or propyleneand an α-olefin having 3 to 8 carbon atoms, or a styrene-basedthermoplastic elastomer having a styrene skeleton.

A modifier according to claim 3 is the modifier according to claim 1 or2, wherein when a total of the polyamide resin and the modifiedelastomer is 100% by mass, a content of the polyamide resin is 10% bymass or more but 80% by mass or less.

A modifier according to claim 4 is the modifier according to any one ofclaims 1 to 3, wherein the dispersed phase (B) has a continuous phase(B₁) containing the polyamide resin and a fine dispersed phase (B₂)dispersed in the continuous phase (B₁) and containing the modifiedelastomer.

A modifier according to claim 5 is the modifier according to any one ofclaims 1 to 4, wherein the first polyolefin resin is a blockcopolymerized polyolefin resin having an ethylene block as a dispersedphase.

The present invention is also directed to a method for using themodifier according to claim 1, including mixing 0.5 parts by mass ormore but 70 parts by mass or less of the modifier per 100 parts by massof the first polyolefin resin.

The present invention is also directed to a method for producing themodifier according to claim 1, including

a melt-kneading step in which the second polyolefin resin and amelt-kneaded product of the polyamide resin and the modified elastomerare melt-kneaded.

The present invention is also directed to a carrier for additives foruse in adding an additive to a first polyolefin resin, the carrierincluding:

a continuous phase (A) containing a second polyolefin resin, and adispersed phase (B) dispersed in the continuous phase (A) and containinga polyamide resin and a modified elastomer, wherein

the dispersed phase (B) is composed of a melt-kneaded product of thepolyamide resin and the modified elastomer having a reactive group thatreacts with the polyamide resin, and wherein

when a total of the continuous phase (A) and the dispersed phase (B) is100% by mass, a content of the dispersed phase (B) is 80% by mass orless.

A carrier for additives according to claim 9 is the carrier foradditives according to claim 8, wherein the additive is at least one ofa flame retardant, a flame retardant aid, a filler, a colorant, anantimicrobial agent, an antistatic agent, and a foaming agent.

Advantageous Effects of Invention

When the modifier according to the present invention is blended with afirst polyolefin resin, a thermoplastic resin composition havingexcellent impact resistance and a pellet mixture can be obtained, andfurther a molded body can be obtained using the thermoplastic resincomposition or the pellet mixture.

When the modified elastomer is an olefin-based thermoplastic elastomerhaving, as its skeleton, a copolymer of ethylene or propylene and anα-olefin having 3 to 8 carbon atoms or a styrene-based thermoplasticelastomer having a styrene skeleton, a specific phase structure can bemore reliably obtained, and therefore a thermoplastic resin compositionhaving excellent impact resistance and a pellet mixture can be obtained,and further a molded body can be obtained using the thermoplastic resincomposition or the pellet mixture.

When the total of the polyamide resin and the modified elastomer is 100%by mass and the content of the polyamide resin is 10% by mass or morebut 80% by mass or less, a specific phase structure can be more stablyobtained, and therefore a thermoplastic resin composition havingexcellent impact resistance and a pellet mixture can be obtained, andfurther a molded body can be obtained using the thermoplastic resincomposition or the pellet mixture.

When the dispersed phase (B) has a continuous phase (B₁) containing thepolyamide resin and a fine dispersed phase (B₂) dispersed in thecontinuous phase (B₁) and containing the modified elastomer, a multiplephase structure is formed, and therefore a thermoplastic resincomposition having more excellent impact resistance and a pellet mixturecan be obtained, and further a molded body can be obtained using thethermoplastic resin composition or the pellet mixture.

When the first polyolefin resin is a block copolymerized polyolefinresin having an ethylene block as a dispersed phase, and at least partof the ethylene block is aggregated at the interface between thecontinuous phase (A) and the dispersed phase (B), a multiple phasestructure is formed, and therefore a thermoplastic resin compositionhaving excellent impact resistance and a pellet mixture can be obtained,and further a molded body can be obtained using the thermoplastic resincomposition or the pellet mixture.

According to the method for using the modifier of the present inventionand the method for producing the modifier of the present invention, thefirst polyolefin resin is modified so that a thermoplastic resincomposition having excellent impact resistance and a pellet mixture canbe obtained, and further a molded body can be obtained using thethermoplastic resin composition or the pellet mixture. Further, sincethe component that imparts impact resistance is prepared separately fromthe first polyolefin resin, a molded body can be obtained by applying aheat load to the first polyolefin resin only once during molding, whichresults in a reduction in the heat history of the molded body.

The carrier for additives according to the present invention makes itpossible to blend an additive with the first polyolefin resin at anaccurate ratio and to obtain a thermoplastic resin composition and amolded body that have improved impact resistance.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a graph showing a correlation between Charpy impact strengthand flexural modulus of each of the test specimens for evaluation ofExamples 1 to 3 and Comparative Examples 1 to 3.

FIG. 2 is an image obtained by observing a thin sample cut out from thetest specimen for evaluation of Example 3 with a transmission electronmicroscope.

DESCRIPTION OF EMBODIMENTS

The particulars shown herein are by way of example and for purposes ofillustrative discussion of embodiments of the present invention, and arepresented in the cause of providing what is believed to be the mostuseful and readily understood description of the principles andconceptual aspects of the present invention. In this regard, no attemptis made to show structural details of the present invention in moredetail than is necessary for a fundamental understanding of the presentinvention, and the description taken with the drawings makes apparent tothose skilled in the art how the several forms of the present inventionmay be embodied in practice.

A modifier according to the present invention is a modifier that can beadded to a first polyolefin resin to obtain a molded body havingimproved impact resistance, the modifier including:

a continuous phase (A) containing a second polyolefin resin, and adispersed phase (B) dispersed in the continuous phase (A) and containinga polyamide resin and a modified elastomer, wherein

the dispersed phase (B) is composed of a melt-kneaded product of thepolyamide resin and the modified elastomer having a reactive group thatreacts with the polyamide resin, and wherein

when a total of the continuous phase (A) and the dispersed phase (B) is100% by mass, a content of the dispersed phase (B) is 80% by mass orless.

Further, when the modifier is blended with the first polyolefin resin, athermoplastic resin composition that is a modified polyolefinresin-based composition can be obtained. Further, when thisthermoplastic resin composition is molded, a modified molded body can beobtained. Further, when the first polyolefin resin is molded togetherwith the modifier (e.g., when a dry blend of pellets is molded), amodified molded body can be obtained. In any case, as described above,the modifier can finally modify a resulting molded body.

A thermoplastic resin composition obtained using the modifier and amolded body using the same have a continuous phase (A′) containing afirst polyolefin resin and a second polyolefin resin and

a dispersed phase (B) dispersed in the continuous phase (A′) andcontaining a polyamide resin and a modified elastomer, wherein

the dispersed phase (B) is composed of a melt-kneaded product of thepolyamide resin and the modified elastomer having a reactive group thatreacts with the polyamide resin.

[1] Modifier

(1) Second Polyolefin Resin

The “second polyolefin resin” (hereinafter, also simply referred to as a“second polyolefin”) is an olefin homopolymer and/or an olefincopolymer. In the modifier, this second polyolefin resin is contained inthe continuous phase (A) and forms the continuous phase (A). Further, inthe thermoplastic resin composition obtained using the modifier and themolded body, the second polyolefin resin is contained in the continuousphase (A′) together with the first polyolefin resin and forms thecontinuous phase (A′).

An olefin constituting the second polyolefin is not particularlylimited, and examples thereof include ethylene, propylene, 1-butene,3-methyl-1-butene, 1-pentene, 3-methyl-1-pentene, 4-methyl-1-pentene,1-hexene, and 1-octene. These olefins may be used singly or incombination of two or more of them.

Specific examples of the polyolefin resin include a polyethylene resin,a polypropylene resin, poly-1-butene, poly-1-hexene, andpoly-4-methyl-1-pentene. These polymers may be used singly or incombination of two or more of them. That is, the polyolefin resin may bea mixture of two or more of the above polymers.

Examples of the polyethylene resin include an ethylene homopolymer and acopolymer of ethylene and another olefin. Examples of the latter includean ethylene-1-butene copolymer, an ethylene-1-hexene copolymer, anethylene-1-octene copolymer, and an ethylene-4-methyl-1-pentenecopolymer (the content of an ethylene-derived structural unit is 50% ormore of the total structural units).

Examples of the polypropylene resin include a propylene homopolymer anda copolymer of propylene and another olefin.

Examples of another olefin constituting the copolymer of propylene andanother olefin include the above-mentioned various olefins (except forpropylene). Among them, for example, ethylene and 1-butene arepreferred. That is, the copolymer of propylene and another olefin ispreferably a propylene-ethylene copolymer or a propylene-1-butenecopolymer.

Further, the copolymer of propylene and another olefin may be either arandom copolymer or a block copolymer. Among them, a block copolymer ispreferred in terms of excellent impact resistance. Particularly, apropylene-ethylene block copolymer having ethylene as another olefin ispreferred. This propylene-ethylene block copolymer is a blockcopolymerized polypropylene having an ethylene block as a dispersedphase. More specifically, the propylene-ethylene block copolymer is apolypropylene resin having a continuous phase composed ofhomopolypropylene and a dispersed phase present in the continuous phaseand containing polyethylene. Such a block copolymerized polypropylenehaving an ethylene block as a dispersed phase is also called, forexample, an impact copolymer, a polypropylene impact copolymer, aheterophasic polypropylene, or a heterophasic block polypropylene. Thisblock copolymerized polypropylene is preferred in terms of excellentimpact resistance.

It is to be noted that the content of a propylene-derived structuralunit of the copolymer of propylene and another olefin is 50% or more ofthe total structural units.

The weight-average molecular weight (based on polystyrene standards) ofthe second polyolefin resin measured by gel permeation chromatography(GPC) is not particularly limited, and may be, for example, 10,000 ormore but 500,000 or less, but is preferably 100,000 or more but 450,000or less, more preferably 200,000 or more but 400,000 or less.

It is to be noted that the second polyolefin resin are polyolefins thathave no affinity for the polyamide resin, which will be described later,and that have no reactive group capable of reacting with the polyamideresin, either. The first and second polyolefin resins are different inthis point from an olefin-based component as the modified elastomer thatwill be described later.

(2) Polyamide Resin

The “polyamide resin” is a polymer having a chain-like skeleton formedby polymerizing a plurality of monomers via amide bonds (—NH—CO—). Inthe modifier, this polyamide resin is contained in the dispersed phase(B) together with the modified elastomer. Further, in the thermoplasticresin composition obtained using the modifier and the molded body, thepolyamide resin forms the dispersed phase (B) in the continuous phase(A′) containing both the first and second polyolefin resins.

Examples of a monomer constituting the polyamide resin include: aminoacids such as 6-aminocaproic acid, 11-aminoundecanoic acid,12-aminododecanoic acid, and para-aminomethylbenzoic acid; and lactamssuch as ε-caprolactam, undecane lactam, and ω-lauryllactam. Thesemonomers may be used singly or in combination of two or more of them.

Further, the polyamide resin can be obtained also by copolymerization ofa diamine and a dicarboxylic acid. In this case, examples of the diamineas a monomer include: aliphatic diamines such as ethylenediamine,1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane,1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane,1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane,1,13-diaminotridecane, 1,14-diaminotetradecane, 1,15-diaminopentadecane,1,16-diaminohexadecane, 1,17-diaminoheptadecane, 1,18-diaminooctadecane,1,19-diaminononadecane, 1,20-diaminoeicosane,2-methyl-1,5-diaminopentane, and 2-methyl-1,8-diaminooctane; alicyclicdiamines such as cyclohexanediamine and bis-(4-aminocyclohexyl) methane;and aromatic diamines such as xylylenediamines (e.g., p-phenylenediamineand m-phenylenediamine). These diamines may be used singly or incombination of two or more of them.

Further, examples of the dicarboxylic acid as a monomer include:aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinicacid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaicacid, sebacic acid, undecanedioic acid, dodecanedioic acid, brasylicacid, tetradecanedioic acid, pentadecanedioic acid, and octadecanedioicacid; alicyclic dicarboxylic acids such as cyclohexanedicarboxylicacids; and aromatic dicarboxylic acids such as phthalic acid,terephthalic acid, isophthalic acid, and naphthalene dicarboxylic acid.These dicarboxylic acids may be used singly or in combination of two ormore of them.

Specific examples of the polyamide resin include polyamide 6, polyamide66, polyamide 11, polyamide 610, polyamide 612, polyamide 614, polyamide12, polyamide 6T, polyamide 61, polyamide 9T, polyamide M5T, polyamide1010, polyamide 1012, polyamide 10T, polyamide MXD6, polyamide 6T/66,polyamide 6T/61, polyamide 6T/61/66, polyamide 6T/2M-5T, and polyamide9T/2M-8T. These polyamides may be used singly or in combination of twoor more of them.

In the present invention, among the above-described various polyamideresins, plant-derived polyamide resins can be used. Plant-derivedpolyamide resins are preferred from the viewpoint of environmentalprotection (particularly from the viewpoint of carbon neutral) becausethey are resins using monomers derived from plant-derived componentssuch as vegetable oils.

Examples of the plant-derived polyamide resins include polyamide 11(hereinafter, also simply referred to as “PA11”), polyamide 610(hereinafter, also simply referred to as “PA610”), polyamide 612(hereinafter, also simply referred to as “PA612”), polyamide 614(hereinafter, also simply referred to as “PA614”), polyamide 1010(hereinafter, also simply referred to as “PA1010”), polyamide 1012(hereinafter, also simply referred to as “PA1012”), and polyamide 10T(hereinafter, also simply referred to as “PA10T”). These plant-derivedpolyamide resins may be used singly or in combination of two or more ofthem.

Among the above, PA11 has a structure in which monomers having 11 carbonatoms are linked via amide bonds. PA11 can be obtained usingaminoundecanoic acid derived from castor oil as a monomer. The contentof a structural unit derived from the monomer having 11 carbon atoms inPA11 is preferably 50% or more or may be 100% of all the structuralunits of PA11.

PA610 has a structure in which monomers having 6 carbon atoms andmonomers having 10 carbon atoms are linked via amide bonds. PA610 can beobtained using sebacic acid derived from castor oil as a monomer. Thetotal content of a structural unit derived from the monomer having 6carbon atoms and a structural unit derived from the monomer having 10carbon atoms in PA610 is preferably 50% or more or may be 100% of allthe structural units of PA610.

PA1010 has a structure in which a diamine having 10 carbon atoms and adicarboxylic acid having 10 carbon atoms are copolymerized. PA1010 canbe obtained using 1,10-decanediamine (decamethylenediamine) and sebacicacid, which are derived from castor oil, as monomers. The total contentof a structural unit derived from the diamine having 10 carbon atoms anda structural unit derived from the dicarboxylic acid having 10 carbonatoms in PA1010 is preferably 50% or more or may be 100% of all thestructural units of PA1010.

PA614 has a structure in which monomers having 6 carbon atoms andmonomers having 14 carbon atoms are linked via amide bonds. PA614 can beobtained using a plant-derived dicarboxylic acid having 14 carbon atomsas a monomer. The total content of a structural unit derived from themonomer having 6 carbon atoms and a structural unit derived from themonomer having 14 carbon atoms in PA614 is preferably 50% or more or maybe 100% of all the structural units of PA614.

PA10T has a structure in which a diamine having 10 carbon atoms andterephthalic acid are linked via amide bonds. PA10T can be obtainedusing 1,10-decanediamine (decamethylenediamine) derived from castor oilas a monomer. The total content of a structural unit derived from thediamine having 10 carbon atoms and a structural unit derived fromterephthalic acid is preferably 50% or more or may be 100% of all thestructural units of PA10T.

Among the above five plant-derived polyamide resins, PA11 is superior tothe other four plant-derived polyamide resins in terms of low waterabsorbability, low specific gravity, and high biomass degree.

Polyamide 610 is inferior to PA11 in water absorption rate, chemicalresistance, and impact strength, but is excellent in heat resistance(melting point) and rigidity (strength). Further, polyamide 610 issuperior to polyamide 6 or polyamide 66 in terms of low waterabsorbability and excellent size stability, and therefore can be used asan alternative to polyamide 6 or polyamide 66.

Polyamide 1010 is superior to PA11 in heat resistance and rigidity.Further, the biomass degree of polyamide 1010 is comparable to that ofPA11 and therefore polyamide 1010 can be used for parts required to havehigher durability.

Polyamide 10T has an aromatic ring in its molecular framework, andtherefore has a higher melting point and higher rigidity than polyamide1010. Therefore, polyamide 10T can be used in harsh environments (partsrequired to have heat resistance, parts on which a force is to beexerted).

(3) Modified Elastomer

The “modified elastomer” is an elastomer having a reactive group thatreacts with the polyamide resin. In the modifier, this modifiedelastomer is contained in the dispersed phase (B) together with thepolyamide resin.

Further, in the thermoplastic resin composition obtained using themodifier and the molded body, the modified elastomer forms the dispersedphase (B) together with the polyamide resin in the continuous phase (A′)containing both the first and second polyolefin resins.

Further, the modified elastomer is preferably a component having anaffinity for the second polyolefin resin. More specifically, themodified elastomer preferably has compatibilizing effect on thepolyamide resin and the second polyolefin resin. In other words, themodified elastomer is preferably a compatibilizer for the polyamideresin and the second polyolefin resin.

Examples of the reactive group include an acid anhydride group(—CO—O—OC—), a carboxyl group (—COOH), an epoxy group {—C₂O (athree-membered ring structure composed of two carbon atoms and oneoxygen atom)}, an oxazoline group (—C₃H₄NO), and an isocyanate group(—NCO). These reactive groups may be used singly or in combination oftwo or more of them.

The amount of modification of the modified elastomer is not limited, andthe modified elastomer only needs to have one or more reactive groupsper molecule. Further, the modified elastomer preferably has 1 or morebut 50 or less reactive groups, more preferably 3 or more but 30 or lessreactive groups, particularly preferably 5 or more but 20 or lessreactive groups per molecule.

Examples of the modified elastomer include: a polymer using any monomercapable of introducing a reactive group (a modified elastomer obtainedby polymerization using a monomer capable of introducing a reactivegroup); an oxidative degradation product of any polymer (a modifiedelastomer having a reactive group formed by oxidative degradation), anda graft polymer obtained by graft polymerization of an organic acid onany polymer (a modified elastomer having a reactive group introduced bygraft polymerization of an organic acid). These modified elastomers maybe used singly or in combination of two or more of them. These modifiedelastomers may be used singly or in combination of two or more of them.

Examples of the monomer capable of introducing a reactive group include:a monomer having a polymerizable unsaturated bond and an acid anhydridegroup; a monomer having a polymerizable unsaturated bond and a carboxylgroup; and a monomer having a polymerizable unsaturated bond and anepoxy group.

Specific examples thereof include: acid anhydrides such as maleicanhydride, itaconic anhydride, succinic anhydride, glutaric anhydride,adipic anhydride, citraconic anhydride, tetrahydrophthalic anhydride,butenyl succinic anhydride; and carboxylic acids such as maleic acid,itaconic acid, fumaric acid, acrylic acid, and methacrylic acid. Thesecompounds may be used singly or in combination of two or more of them.Among these compounds, an acid anhydride is preferred, maleic anhydrideand itaconic anhydride are more preferred, and maleic anhydride isparticularly preferred.

Further, the type of resin constituting the skeleton of the modifiedelastomer (hereinafter, referred to as a “skeletal resin”) is notparticularly limited, and various thermoplastic resins can be used. Asthis skeletal resin, one or two or more of the various resins mentionedabove as examples of the polyolefin resin can be used.

In addition, the skeletal resin may be an olefin-based thermoplasticelastomer or a styrene-based thermoplastic elastomer. Thesethermoplastic elastomers may be used singly or in combination of two ormore of them.

Examples of the olefin-based thermoplastic elastomer include copolymersof two or more of olefins.

Examples of the olefins include ethylene, propylene, and α-olefinshaving 4 to 8 carbon atoms. Examples of the α-olefin having 4 to 8carbon atoms include 1-butene, 3-methyl-1-butene, 1-pentene,3-methyl-1-pentene, 4-methyl-1-pentene, 1-hexene, and 1-octene. Amongsuch olefin-based thermoplastic elastomers, a copolymer of ethylene andan α-olefin having 3 to 8 carbon atoms and a copolymer of propylene andan α-olefin having 4 to 8 carbon atoms are preferred.

Specific examples of the copolymer of ethylene and an α-olefin having 3to 8 carbon atoms include ethylene-propylene copolymers (EPR),ethylene-1-butene copolymers (EBR), ethylene-1-pentene copolymers, andethylene-1-octene copolymers (EOR). Specific examples of the copolymerof propylene and an α-olefin having 4 to 8 carbon atoms includepropylene-1-butene copolymers (PBR), propylene-1-pentene copolymers, andpropylene-1-octene copolymers (POR). These copolymers may be used singlyor in combination of two or more of them.

On the other hand, examples of the styrene-based thermoplastic elastomerinclude: a block copolymer of a styrene-based compound and a conjugateddiene compound; and a hydrogenated product thereof.

Examples of the styrene-based compound include: styrene; alkylstyrenessuch as α-methylstyrene, p-methylstyrene, and p-t-butylstyrene;p-methoxystyrene; and vinylnaphthalene. These styrene-based compoundsmay be used singly or in combination of two or more of them.

Examples of the conjugated diene compound include butadiene, isoprene,piperylene, methylpentadiene, phenylbutadiene,3,4-dimethyl-1,3-hexadiene, and 4,5-diethyl-1,3-octadiene. Theseconjugated diene compounds may be used singly or in combination of twoor more of them.

Specific examples of the styrene-based thermoplastic elastomer includestyrene-butadiene-styrene copolymers (SBS), styrene-isoprene-styrenecopolymers (SIS), styrene-ethylene/butylene-styrene copolymers (SEBS),and styrene-ethylene/propylene-styrene copolymers (SEPS). Thesestyrene-based thermoplastic elastomers may be used singly or incombination of two or more of them. Among them, SEBS is preferred.

The molecular weight of the modified elastomer is not particularlylimited, but the weight-average molecular weight of the modifiedelastomer is preferably 10,000 or more but 500,000 or less, morepreferably 35,000 or more but 500,000 or less, particularly preferably35,000 or more but 300,000 or less. It is to be noted that theweight-average molecular weight is measured by a GPC method (based onpolystyrene standards).

(4) Other Components that May be Contained in Modifier

The modifier may contain, in addition to the second polyolefin resin,the polyamide resin, and the modified elastomer, other components suchas another thermoplastic resin. The other components may be used singlyor in combination of two or more of them.

Examples of another thermoplastic resin include polyester-based resins(polybutylene terephthalate, polyethylene terephthalate, polycarbonate,polybutylene succinate, polyethylene succinate, and polylactic acid).These thermoplastic resins may be used singly or in combination of twoor more of them.

(5) Phase Structure of Modifier

In the modifier, the second polyolefin resin forms a continuous phase(A). Further, the polyamide resin and the modified elastomer form adispersed phase (B). The dispersed phase (B) is dispersed in thecontinuous phase (A). Such a phase structure can be obtained as athermoplastic resin obtained by melt-kneading the second polyolefinresin and a melt-kneaded product of the polyamide resin and the modifiedelastomer.

Further, in the modifier, the polyamide resin constituting the dispersedphase (B), which is composed of the polyamide resin and the modifiedelastomer, forms a continuous phase (B₁) in the dispersed phase (B), andat least the modified elastomer out of the polyamide resin and themodified elastomer can form a fine dispersed phase (B₂) in the dispersedphase (B). When having such a multiple phase structure in which a finedispersed phase (B₂) is present in a dispersed phase (B), thethermoplastic resin composition and the molded body can have moreexcellent impact resistance.

Further, in the modifier, when the second polyolefin resin is a blockcopolymerized polyolefin resin having an ethylene block as a dispersedphase, at least part of the ethylene block constituting the blockcopolymerized polyolefin resin can be aggregated at the interfacebetween the continuous phase (A) and the dispersed phase (B) in themolded body. Also when having such a phase structure, the thermoplasticresin composition and the molded body can have more excellent impactresistance.

The size of the dispersed phase (B) contained in the continuous phase(A) of the modifier is not particularly limited, but the averagediameter (average particle diameter) of the dispersed phase (B) ispreferably 10000 nm or less, more preferably 50 nm or more but 8000 nmor less, even more preferably 100 nm or more but 4000 nm or less. Theaverage diameter of the dispersed phase (B) is the average of maximumlengths (nm) of 50 particles of the dispersed phase (B) randomlyselected on an image obtained using an electron microscope.

The size of the fine dispersed phase (B₂) contained in the dispersedphase (B) of the modifier is not particularly limited, but the averagediameter (average particle diameter) of the fine dispersed phase (B₂) ispreferably 5 nm or more but 1000 nm or less, more preferably 5 nm ormore but 600 nm or less, even more preferably 10 nm or more but 400 nmor less, particularly preferably 15 nm or more but 350 nm or less. Theaverage diameter of the fine dispersed phase (B₂) is the average ofmaximum lengths (nm) of 100 particles of the fine disperse phases (B₂)randomly selected on an image obtained using an electron microscope.

(6) Blending Ratio

When the total of the continuous phase (A) and the dispersed phase (B)in the modifier is 100% by mass, the content of the dispersed phase (B)is 80% by mass or less. More specifically, when the amount of the secondpolyolefin resin is defined as W_(A), the total amount of the polyamideresin and the modified elastomer is defined as W_(B), and the total ofW_(A) and W_(B) is 100% by mass, the ratio of W_(B) is usually 80% bymass or less (usually 0.5% by mass or more). When the ratio of W_(B) iswithin the above range, excellent impact resistance and an excellentbalance between rigidity and moldability can be achieved. The ratio ofW_(B) is preferably 5% by mass or more but 78% by mass or less, morepreferably 10% by mass or more but 77% by mass or less, even morepreferably 23% by mass or more but 76% by mass or less, even still morepreferably 30% by mass or more but 75% by mass or less, particularlypreferably 33% by mass or more but 72% by mass or less, moreparticularly preferably 35% by mass or more but 67% by mass or less,even more particularly preferably 37% by mass or more but 63% by mass orless.

In addition, when the total of the polyamide resin and the modifiedelastomer is 100% by mass, the content of the polyamide resin may be 10%by mass or more but 80% by mass or less. When the content of thepolyamide resin is within the above range, a phase structure can beobtained in which the second polyolefin resin forms a continuous phase(A) and the polyamide resin forms a dispersed phase (B). This makes itpossible to obtain a thermoplastic resin composition and a molded bodythat offer excellent impact resistance and excellent rigidity. Thecontent of the polyamide resin is preferably 12% by mass or more but 78%by mass or less, more preferably 14% by mass or more but 75% by mass orless, even more preferably 25% by mass or more but 73% by mass or less,even more preferably 30% by mass or more but 71% by mass or less,particularly preferably 34% by mass or more but 68% by mass or less,more particularly preferably 40% by mass or more but 64% by mass orless. When the content of the polyamide resin is within the above range,the polyamide resin and the modified elastomer can be dispersed assmaller particles of the dispersed phase (B) in the continuous phase(A). Further, the amount of the polyamide resin, which has a largespecific gravity, to be used can be reduced to reduce the specificgravity of the thermoplastic resin composition and the molded body. Thisallows the thermoplastic resin composition and the molded body to haveexcellent impact resistance and rigidity while being lightweight.

Further, as described above, since the content of the polyamide resincan be reduced while the mechanical characteristics are well maintained,the thermoplastic resin composition and the molded body can haverelaxing appearance with low surface luster. Therefore, the molded bodycan be applied to exterior and interior materials that are directlyvisually recognized, and can offer excellent design flexibility.

It is to be noted that from the viewpoint of obtaining a polyamiderich-type modifier whose polyamide resin content is 50% by mass or more,the content of the polyamide resin may be 50% by mass or more but 80% bymass or less when the total of the polyamide resin and the modifiedelastomer is 100% by mass.

Further, when the total of the second polyolefin resin and the polyamideresin is 100% by mass, the content of the polyamide resin may be 60% bymass or less (usually 1% by mass or more). The content of the polyamideresin is preferably 5% by mass or more but 55% by mass or less, morepreferably 15% by mass or more but 53% by mass or less, even morepreferably 19% by mass or more but 50% by mass or less, even still morepreferably 21% by mass or more but 48% by mass or less, particularlypreferably 23% by mass or more but 46% by mass or less, moreparticularly preferably 25% by mass or more but 44% by mass or less,even more particularly preferably 28% by mass or more but 43% by mass orless.

Further, when the total of the second polyolefin resin, the polyamideresin, and the modified elastomer is 100% by mass, the content of thepolyamide resin may be 1% by mass or more but 60% by mass or less. Thecontent of the polyamide resin is preferably 3% by mass or more but 50%by mass or less, more preferably 5% by mass or more but 45% by mass orless, even more preferably 7% by mass or more but 40% by mass or less,even more preferably 9% by mass or more but 35% by mass or less,particularly preferably 12% by mass or more but 30% by mass or less.

Further, when the total of the second polyolefin resin, the polyamideresin, and the modified elastomer is 100% by mass, the content of themodified elastomer may be 1% by mass or more but 70% by mass or less.When the content of the modified elastomer is within the above range, athermoplastic resin composition and a molded body that have excellentimpact resistance and excellent rigidity can be obtained. The content ofthe modified elastomer is preferably 2% by mass or more but 65% by massor less, more preferably 3% by mass or more but 60% by mass or less,even more preferably 5% by mass or more but 55% by mass or less, evenstill more preferably 7% by mass or more but 50% by mass or less,particularly preferably 13% by mass or more but 47% by mass or less,more particularly preferably 17% by mass or more but 45% by mass orless.

[2] Thermoplastic Resin Composition and Molded Body

The modifier can be added to a first polyolefin resin to obtain athermoplastic resin composition and a molded body. The modifier canimprove the impact resistance of the thus obtained thermoplastic resincomposition and molded body.

(1) First Polyolefin Resin

The “first polyolefin resin” (hereinafter, also simply referred to as a“first polyolefin”) is an olefin homopolymer and/or an olefin copolymer.In the thermoplastic resin composition obtained using the modifier andthe molded body, the first polyolefin resin is contained in thecontinuous phase (A′) together with the second polyolefin resin andforms the continuous phase (A′).

An olefin constituting the first polyolefin is not particularly limited,and examples thereof include the same olefins as mentioned above withreference to the second polyolefin.

The weight-average molecular weight (based on polystyrene standards) ofthe first polyolefin resin measured by gel permeation chromatography(GPC) is not particularly limited, and may be, for example, 10,000 ormore but 500,000 or less, but is preferably 100,000 or more but 450,000or less, more preferably 200,000 or more but 400,000 or less.

It is to be noted that the first polyolefin resin is a polyolefin thathas no affinity for the above-described polyamide resin and that has noreactive group capable of reacting with the polyamide resin, either. Thefirst polyolefin resin is different in this point from an olefin-basedcomponent as the above-described modified elastomer.

The first polyolefin and the second polyolefin may be the same resin ordifferent resins.

When the first polyolefin and the second polyolefin are differentresins, for example, one of the first polyolefin and the secondpolyolefin is a block copolymerized polyolefin resin (e.g., a blockcopolymerized polypropylene resin) having an ethylene block as adispersed phase, and the other is a non-block copolymerized polyolefinresin.

In this case, in terms of impact resistance, it is preferred that thefirst polyolefin be a block copolymerized polypropylene resin having anethylene block as a dispersed phase, and the second polyolefin be anon-block copolymerized polyolefin resin. Further, the non-blockcopolymerized polyolefin resin is preferably a homopolypropylene resin.

In the above described case where the first polyolefin is a blockcopolymerized polypropylene resin having an ethylene block as adispersed phase, and the second polyolefin is a non-block copolymerizedpolypropylene resin, the thermoplastic resin composition obtained usingthe modifier and the molded body have a continuous phase (A′) formed ofhomopolypropylene constituting the first polypropylene resin and thesecond polypropylene resin, a dispersed phase (B) dispersed in thecontinuous phase (A′) and containing the polyamide resin and themodified elastomer, and a dispersed phase (B′) composed of the ethyleneblock constituting the first polypropylene resin. In addition, at leastpart of the ethylene block is aggregated at the interface between thecontinuous phase (A′) and the dispersed phase (B). This allows thethermoplastic resin composition and the molded body to offerparticularly excellent impact resistance.

(2) Other Components that May be Contained in Thermoplastic ResinComposition and Molded Body

The thermoplastic resin composition obtained using the modifier and themolded body may contain, in addition to the first polyolefin resin, thesecond polyolefin resin, the polyamide resin, and the modifiedelastomer, various additives such as another thermoplastic resin, aflame retardant, a flame retardant aid, a filler, a colorant, anantimicrobial agent, and an antistatic agent. These additives may beused singly or in combination of two or more of them.

Examples of another thermoplastic resin include polyester-based resins(polybutylene terephthalate, polyethylene terephthalate, polycarbonate,polybutylene succinate, polyethylene succinate, and polylactic acid).These thermoplastic resins may be used singly or in combination of twoor more of them.

Examples of the flame retardant include halogen-based flame retardants(halogenated aromatic compounds), phosphorus-based flame retardants(e.g., nitrogen-containing phosphate compounds, phosphoric acid esters),nitrogen-based flame retardants (e.g., guanidine, triazine, melamine,and derivatives thereof), inorganic flame retardants (e.g., metalhydroxides), boron-based flame retardants, silicone-based flameretardants, sulfur-based flame retardants, and red phosphorus-basedflame retardants. These flame retardants may be used singly or incombination of two or more of them.

Examples of the flame retardant aid include various antimony compounds,metal compounds containing zinc, metal compounds containing bismuth,magnesium hydroxide, and clayey silicate. These flame retardant aids maybe used singly or in combination of two or more of them.

Examples of the filler include: glass components (e.g., glass fibers,glass beads, glass flakes); silica; inorganic fibers (glass fibers,alumina fibers, carbon fibers); graphite; silicate compounds (e.g.,calcium silicate, aluminum silicate, kaolin, talc, clay); metal oxides(e.g., iron oxide, titanium oxide, zinc oxide, antimony oxide, alumina);carbonates and sulfates of metals such as calcium, magnesium, and zinc;and organic fibers (e.g., aromatic polyester fibers, aromatic polyamidefibers, fluororesin fibers, polyimide fibers, vegetable fibers). Thesefillers may be used singly or in combination of two or more of them.

Examples of the colorant include pigments and dyes. These colorants maybe used singly or in combination of two or more of them.

(3) Phase Structure of Thermoplastic Resin Composition and Molded Body

In the thermoplastic resin composition obtained using the modifier andthe molded body, the first polyolefin resin and the second polyolefinresin form a continuous phase (A′). That is, the modifier has acontinuous phase (A) containing the second polyolefin, but in thethermoplastic resin composition and the molded body, the firstpolyolefin resin and the continuous phase (A) are integrated to form acontinuous phase (A′).

On the other hand, the polyamide resin and the modified elastomerusually form a dispersed phase (B) as in the case of the inside of themodifier. That is, the dispersed phase (B) is dispersed in thecontinuous phase (A′). This phase structure is obtained by molding athermoplastic resin that is a mixture of the modifier and the firstpolyolefin resin.

Further, in the thermoplastic resin composition obtained using themodifier and the molded body, the polyamide resin constituting thedispersed phase (B), which is composed of the polyamide resin and themodified elastomer, forms a continuous phase (B₁) in the dispersed phase(B), and at least the modified elastomer out of the polyamide resin andthe modified elastomer can form a fine dispersed phase (B₂) in thedispersed phase (B). When having such a multiple phase structure inwhich a fine dispersed phase (B₂) is further present in a dispersedphase (B), the thermoplastic resin composition and the molded body canhave more excellent impact resistance. When already formed in themodifier, the multiple phase structure is basically maintained also inthe thermoplastic resin composition obtained using the modifier and themolded body.

Further, when the first polyolefin resin is a block copolymerizedpolyolefin resin having an ethylene block as a dispersed phase, at leastpart of the ethylene block constituting the block copolymerizedpolyolefin resin can be aggregated at the interface between thecontinuous phase (A′) and the dispersed phase (B) in the thermoplasticresin composition obtained using the modifier and the molded body. Also,when having such a phase structure, the thermoplastic resin compositionand the molded body can have more excellent impact resistance.

The size of the dispersed phase (B) contained in the continuous phase(A′) of the thermoplastic resin composition obtained using the modifierand the molded body is not particularly limited, but is usually the sameas that of the dispersed phase (B) in the modifier described above.

Further, when the fine dispersed phase (B₂) is contained in thedispersed phase (B) of the thermoplastic resin composition obtainedusing the modifier and the molded body, the size of the fine dispersedphase (B₂) is not particularly limited, but is usually the same as thatof the fine disperse phase (B₂) in the modifier described above.

(4) Blending Ratio

When the total of the continuous phase (A′) and the dispersed phase (B)in the thermoplastic resin composition obtained using the modifier andthe molded body is 100% by mass, the content of the dispersed phase (B)is 80% by mass or less. More specifically, when the total amount of thefirst polyolefin resin and the second polyolefin resin is defined asW_(A′), the total amount of the polyamide resin and the modifiedelastomer is defined as W_(B), and the total of W_(A′) and W_(B) is 100%by mass, the ratio of W_(B) is usually 80% by mass or less (usually 0.5%by mass or more). When the ratio of W_(B) is within the above range,excellent impact resistance and an excellent balance between rigidityand moldability can be achieved. The ratio of W_(B) is preferably 5% bymass or more but 78% by mass or less, more preferably 10% by mass ormore but 77% by mass or less, even more preferably 23% by mass or morebut 76% by mass or less, even still more preferably 30% by mass or morebut 75% by mass or less, particularly preferably 33% by mass or more but72% by mass or less, more particularly preferably 35% by mass or morebut 67% by mass or less, even more particularly preferably 37% by massor more but 63% by mass or less.

Further, the content of each of the first polyolefin resin and thesecond polyolefin resin is not particularly limited. However, when thetotal of the first polyolefin resin and the second polyolefin resin is100% by mass, the content of the second polyolefin resin is preferably40% by mass or less. The content of the second polyolefin resin is morepreferably 1% by mass or more but 30% by mass or less, particularlypreferably 3% by mass or more but 25% by mass or less.

The specific gravity of the thermoplastic resin composition obtainedusing the modifier and the molded body is not particularly limited, butmay usually be 1.05 or less. When the thermoplastic resin compositionand the molded body have a polyamide resin content of 1% by mass or morebut 40% by mass or less, a polypropylene resin content of 50% by mass ormore but 75% by mass or less, and a maleic anhydride-modifiedolefin-based thermoplastic elastomer content of 5% by mass or more but30% by mass or less, the specific gravity of the thermoplastic resincomposition and the molded body may particularly be 0.89 or more but1.05 or less, and may more particularly be 0.92 or more but 0.98 orless. That is, even when having the specific gravity equivalent to thoseof a polyethylene resin and a polypropylene resin, the thermoplasticresin composition and the molded body can offer much more excellentimpact resistance and rigidity than these resins.

(5) Types of Molded Bodies

The shape, size, thickness, etc. of the molded body are not particularlylimited, and its application is not particularly limited, either.

The molded body is used as various articles for use in vehicles such asautomobiles, railway vehicles (general railway vehicles), aircraftfuselages (general fuselages), and boats and ships/hulls (generalhulls), and bicycles (general bicycles).

Among them, articles for use in automobiles include exterior parts,interior parts, engine parts, and electrical parts. Specific examples ofthe exterior parts for automobiles include roof rails, fenders, fenderliners, garnishes, bumpers, door panels, roof panels, hood panels, trunklids, fuel lids, door mirror stays, spoilers, hood louvers, wheelcovers, wheel caps, grill apron cover frames, lamp bezels, door handles(pull handles), door moldings, rear finishers, wipers, engine undercovers, floor under covers, rocker moldings, cowl louvers, cowls(motorcycles) and film seat for motor parts.

Specific examples of the interior parts for automobiles include: trimparts such as door trim base materials (FR, RR, BACK), pockets, armrests, switch bases, decorative panels, ornament panels, EA materials,speaker grills, and quarter trim base materials; pillar garnishes; cowlside garnishes (cowl side trims); seat parts such as shields, backboards, dynamic dampers, and side air bag peripheral parts; ceiling;carpet; instrument panel parts such as center clusters, registers,center boxes (doors), glove doors, cup holders, and air bag peripheralparts; center consoles; overhead consoles; sun visors, sun visors systemparts such as sun visor brackets; deck boards (luggage boards); undertrays; package trays; high mount stop lamp covers; CRS covers; seat sidegarnishes; scuff plates; room lamps; assist grips; safety belt parts;register blades; washer levers; window regulator handles; knobs ofwindow regulator handles; and passing light levers.

Specific examples of the engine parts for automobiles include alternatorterminals, alternator connectors, IC regulators, potentiometer bases forlight dimmers, exhaust gas valves, fuel pipes, cooling pipes, brakepipes, wiper pipes, exhaust pipes, intake pipes, hoses, tubes, airintake nozzle snorkels, intake manifolds, fuel pumps, engine coolingwater joints, carburetor main bodies, carburetor spacers, exhaust gassensors, cooling water sensors, oil temperature sensors, brake pad wearsensors, throttle position sensors, crankshaft position sensors, airflow meters, brake pad wear sensors, brake pistons, solenoid bobbins,engine oil filters, and ignitor cases, and torque control levers.

Specific examples of the electrical parts for automobiles includebattery peripheral parts, air conditioner thermostats, hot air flowcontrol valves, brush holders for radiator motors, water pump impellers,turbine vanes, wiper motor-related parts, distributors, starterswitches, starter relays, transmission wire harnesses, window washernozzles, air conditioner panel switch boards, fuel-relatedelectromagnetic valve coils, various connectors such as wire harnessconnectors, SMJ connectors, PCB connectors, door grommet connectors, andfuse connectors, horn terminals, electrical component insulating plates,step motor rotors, lamp sockets, lamp reflectors, lamp housings, cleanercases, filter cases, and power trains.

Further, the molded body is used also as various articles for use inapplications other than the above vehicles. Specific examples thereofinclude: industrial materials such as ropes, spun-bonded fabrics,polishing brushes, industrial brushes, filters, transport containers,trays, transport trolleys, and other general material;

electronic parts such as connectors, coils, sensors, LED lamps, sockets,resistors, relay cases, small switches, coil bobbins, condensers,variable capacitor cases, optical pickups, resonators, various terminalboards, transformers, plugs, printed circuit boards, tuners, speakers,microphones, headphones, compact motors, compact transmission gears,magnetic head bases, power modules, semiconductors, liquid crystals, FDDcarriages, FDD chassis, motor brush holders, parabolic antennas, andcomputer-related parts;

electrical devices such as power generators, electric motors, electrictransformers, current transformers, voltage regulators, rectifiers,inverters, relays, power contacts, switches, breakers, knife switches,multipole rods, electrical part cabinets and electric apparatus film;

industrial robot bodies, nursing-care robot bodies, drone (flyingobjects operated by remote control, flying objects capable ofautonomously flying) bodies,

home appliances and office equipment such as VTR parts, televisionparts, irons, hair dryers, rice cooker parts, microwave oven parts,acoustic parts, audio/LD parts, CD/DVD parts, lighting parts,refrigerator parts, washing machine parts, air conditioner parts,typewriter/word processor parts, office computer parts, PCs, gamemachines, tablet terminals, mobile phones, smart phones, telephones andrelated parts, facsimile parts, copier parts, cleaning/washing devices,motor parts and film seat for the household appliance;

optical and precision instruments such as cameras, clocks, microscopes,binoculars, telescopes, and eyeglasses;

everyday items and housewares such as storage cases (e.g., food trays,storage boxes, storage trays, attache cases, suitcases, helmets, waterbottles, and bottles), toiletries, writing tools, stationery,book-slides, skin-care tools, utensils, tableware, laundry tools,cleaning tools, coat hangers, film for life miscellaneous goods, foodcontainers, and lids (e.g., lids for glass bottles);

entertainment items such as toys;

machine tools/general machinery/machine parts such as mowing machinebodies, covers, power tool bodies, covers, and various clips;

sporting goods such as tennis racket strings, ski plates/boards,protectors (baseball, soccer, motor sports), shoes, shoe soles (shoesoles, soles for sports shoes), outdoor/climbing tools;

furniture-related items such as costume cases, tables, chairs, shoeboxes, kitchen utensils, toilet room goods, bathroom goods, curtain,bedding cover and blanket;

housing and civil engineering-related articles such as interior andexterior walls/roofs, heat insulating materials, door/door-relatedparts, window material-related parts, floor material-related parts,seismic isolating/damping parts, shutters, gutters, water supply andsewage-related parts (lifeline-related parts), parking garages, gas andpower supply-related parts (lifeline-related parts), civil engineeringparts, film and seat for engineering works and house use, trafficsignals, road signs, pylons, center poles, guardrails (guard wires), andequipment for construction works;

medical supplies such as mouthpieces, medical equipment, drug containersand medical film;

clothing items such as uniform, working wear, sportswear, shirt,underwear (including socks), pants, shoes and heavy winterclothing-proof;

agriculture-, forestry-, and fishery-related items such as agriculturalmachinery, farming tools, flower pots (planters), fishing gear, marineculture-related tools, and tools for forestry industry.

Other examples of the molded body include pellets formed into variousshapes.

[3] Method for Producing Modifier

A method for producing the modifier according to the present inventionincludes a melt-kneading step in which the second polyolefin resin and amelt-kneaded product of the polyamide resin and the modified elastomerare melt-kneaded.

The above “melt-kneaded product” is a thermoplastic resin compositionobtained by melt-kneading the polyamide resin and the modifiedelastomer. Examples of each of the polyamide resin and the modifiedelastomer that can be used at this time are the same as those mentionedabove.

The melt-kneaded product can be obtained by melt-kneading both theresins so that when the total of the polyamide resin and the modifiedelastomer is 100% by mass, the blending ratio of the polyamide resin is10% by mass or more but 80% by mass or less. This makes it possible,when the melt-kneaded product and the second polyolefin resin are mixed,to obtain a modifier in which the polyamide resin is dispersed in thesecond polyolefin resin. More specifically, the modifier can have aphase structure in which a continuous phase (A) containing the secondpolyolefin resin is formed, and a dispersed phase (B) containing thepolyamide resin and the modified elastomer is dispersed in thecontinuous phase (A). Further, a multiple phase structure can beobtained in which the dispersed phase (B) has a continuous phase (B₁)containing the polyamide resin and a fine dispersed phase (B₂) dispersedin the continuous phase (B₁) and containing the modified elastomer.

The blending ratio of the polyamide resin is preferably 12% by mass ormore but 78% by mass or less, more preferably 14% by mass or more but75% by mass or less, even more preferably 25% by mass or more but 73% bymass or less, even more preferably 30% by mass or more but 71% by massor less, particularly preferably 34% by mass or more but 68% by mass orless, more particularly preferably 40% by mass or more but 64% by massor less. When the blending ratio of the polyamide resin is within theabove range, a modifier can be obtained in which the polyamide resin isdispersed as smaller particles in the second polyolefin resin.

It is to be noted that from the viewpoint of obtaining a polyamide resinrich-type modifier whose polyamide resin content is 50% by mass or more,the blending ratio of the polyamide resin may be 50% by mass or more but80% by mass or less when the total of the polyamide resin and themodified elastomer is 100% by mass.

A kneading method used to obtain the meld-kneaded product is notparticularly limited. The kneaded product can be obtained by, forexample, using a kneading device such as an extruder (e.g. asingle-screw extruder or a twin-screw extruder), a kneader, or a mixer(e.g., a high-speed flow mixer, a paddle mixer, or a ribbon mixer).These devices may be used singly or in combination of two or more ofthem. When two or more devices are used, they may be operated eithercontinuously or batch-wise. Further, all the components of the kneadedproduct may be mixed at a time or may be mixed by adding them in severalbatches (multistage addition).

Further, the kneading temperature at which the melt-kneaded product isobtained is not particularly limited as long as melt-kneading can beperformed, and the kneading temperature can be appropriately adjustedaccording to the type of each of the components. In particular, it ispreferred that all the resins be kneaded in a molten state. Morespecifically, the kneading temperature may be 190° C. to 350° C., and ispreferably 200° C. to 330° C., more preferably 205° C. to 310° C.

The “melt-kneading step” is a step in which the second polyolefin resinand the melt-kneaded product are melt-kneaded. Examples of the secondpolyolefin resin that can be used at this time are the same as thosementioned above, and the second polyolefin resin can be blended in sucha manner as described above.

A kneading method used to obtain the modifier is not particularlylimited, and the same device, operation mode, and kneading temperatureas described above with reference to a case where the melt-kneadedproduct is obtained may be used.

[4] Method for Using Modifier

A method for using the modifier according to the present inventionincludes mixing 0.5 parts by mass or more but 70 parts by mass or lessof the modifier per 100 parts by mass of the first polyolefin resin.

A molded body raw material obtained by mixing the first polyolefin resinand the modifier in such a manner as described above is usually moldedto obtain a molded body. This makes it possible to obtain a molded bodyexcellent in impact resistance while reducing the heat history load ofthe first polyolefin resin. The blending ratio of the modifier with thefirst polyolefin is preferably 1 part by mass or more but 50 parts bymass or less, more preferably 2 parts by mass or more but 48 parts bymass or less, even more preferably 3 parts by mass or more but 43 partsby mass or less, even still more preferably 4 parts by mass or more but40 parts by mass or less, particularly preferably 5 parts by mass ormore but 35 parts by mass or less.

A method for mixing the modifier and the first polyolefin resin and ameans for performing the method are not particularly limited, but themolded body raw material can be obtained by dry blending using ablender.

Further, as described above, the molded body obtained using the modifiermay contain, in addition to the first polyolefin resin, the secondpolyolefin resin, the polyamide resin, and the modified elastomer,various additives such as a flame retardant, a flame retardant aid, afiller, a colorant, an antimicrobial agent, and an antistatic agent.When these additives are added to the molded body, the modifier can beused as a carrier that carries these additives. Further, the modifiercan be used also as a carrier for blending a foaming agent.

It is to be noted that a method for molding the molded body raw materialis not particularly limited. Examples of the molding method includeinjection molding, extrusion molding (sheet extrusion, profileextrusion), T-die molding, blow molding, injection blow molding,inflation molding, blow molding, vacuum molding, compression molding,press molding, stamping molding, and transfer molding. These moldingmethods may be used singly or in combination of two or more of them.

It is to be noted that a molded body can be obtained by molding themolded body raw material, which has a continuous phase (A′) containing afirst polyolefin resin and a second polyolefin resin and a dispersedphase (B) dispersed in the continuous phase (A) and containing apolyamide resin and a modified elastomer, wherein the dispersed phase(B) is composed of a melt-kneaded product of the polyamide resin and themodified elastomer having a reactive group that reacts with thepolyamide resin, and wherein when a total of the continuous phase (A′)and the dispersed phase (B) is 100% by mass, a content of the dispersedphase (B) is 70% by mass or less, when a total of the first polyolefinresin and the second polyolefin resin is 100% by mass, a content of thesecond polyolefin resin is 70% by mass or less, and a heat history ofthe first polyolefin resin is lower than that of the second polyolefinresin. That is, a molded body can be obtained by molding, as theabove-described thermoplastic resin, a mixture of the first polyolefinresin and the modifier containing the second polyolefin resin, thepolyamide resin, and the modified elastomer.

This molded body obtained using the method described above can offersignificantly excellent impact resistance while well maintainingrigidity that the first polyolefin originally has. Further, a moldedbody in which the heat history of the first polyolefin resin has beensuppressed can be obtained by using, as the first polyolefin resin, partof a polyolefin to be used. That is, a molded body can be obtained bymolding, as the above-described thermoplastic resin, a mixture of thefirst polyolefin resin and the modifier containing the second polyolefinresin, the polyamide resin, and the modified elastomer.

However, at the time of filing the present application, it is impossibleto directly specify the property that the heat history of the firstpolyolefin resin is lower than that of the second polyolefin resin. Evenif possible, it takes too much cost and time to specify such a propertyeven with current analytical techniques, and therefore there areunpractical circumstances in light of the necessity of promptness etc.,due to the nature of patent application.

[5] Carrier for Additives

A carrier for additives according to the present invention is a carrierfor additives for use in adding an additive to a first polyolefin resin,the carrier including:

a continuous phase (A) containing a second polyolefin resin; and adispersed phase (B) dispersed in the continuous phase (A) and containinga polyamide resin and a modified elastomer, wherein

the dispersed phase (B) is composed of a melt-kneaded product of thepolyamide resin and the modified elastomer having a reactive group thatreacts with the polyamide resin, and wherein

when a total of the continuous phase (A) and the dispersed phase (B) is100% by mass, a content of the dispersed phase (B) is 80% by mass orless.

The components of the above-described modifier can directly be used ascomponents of the carrier for additives, and the carrier for additivescan be obtained by blending these components in the same manner asdescribed above with reference to the modifier.

When a molded body is obtained, various additives may be blended with abase resin (in the present invention, the first polyolefin resin).Examples of the additives include a flame retardant, a flame retardantaid, a filler, a colorant, an antimicrobial agent, an antistatic agent,and a foaming agent. The details of the additives described above withreference to the modifier can directly be applied to these additives.

The amount of an additive to be blended is usually smaller than that ofa base resin. Therefore, for the purpose of improving handleability andmore accurately weighing the amount of an additive to be blended, anadditive may be carried by a carrier (carrier for additive) so as to beblended with a base resin together with the carrier. When the base resinis, for example, a polyolefin resin, the carrier for additives to beused is preferably a resin compatible with the polyolefin resin. Whenthe base resin is a polyolefin resin, addition of the carrier foradditives according to the present invention is highly effective atimparting impact resistance even when the amount of the carrier foradditives added is small.

It is to be noted that an additive to be used can be carried by thecarrier for additives by appropriately blending them depending on thetype or shape of the additive.

EXAMPLES

Hereinafter, the present invention will be specifically described withreference to examples.

[1] Production of Molded Bodies for Evaluation

<1> Modifier

A modifier was prepared by the following procedure. The modifiercontained 55% by mass of a second polyolefin, 25% by mass of a polyamideresin, and 20% by mass of a modified elastomer per 100% of its totalmass.

(1) Preparation of Molten Mixture

Pellets of the following polyamide resin and pellets of the followingmodified elastomer were dry-blended, then fed into a twin-screwmelt-kneading extruder (manufactured by TECHNOVEL CORPORATION, screwdiameter: 15 mm, L/D=59), and melt-kneaded under conditions of akneading temperature of 210° C., an extrusion speed of 2.0 kg/hr, and ascrew rotation speed of 200 rpm. The thus obtained melt-kneaded productwas pelletized by a pelletizer to obtain pellets of the melt-kneadedproduct.

Polyamide resin: nylon 11 resin, manufactured by ARKEMA K.K., productname “Rilsan BMN O”, weight-average molecular weight 18,000, meltingpoint 190° C.

Modified elastomer: maleic anhydride-modified ethylene-butene copolymer(modified EBR), manufactured by Mitsui Chemicals, Inc., product name“TAFMER MH7020”, MFR (230° C.)=1.5 g/10 min

(2) Preparation of Modifier

The pellets of the molten mixture obtained in the above (1) and pelletsof the following second polyolefin resin were dry-blended, then fed intoa twin-screw melt-kneading extruder (manufactured by TECHNOVELCORPORATION, screw diameter: 15 mm, L/D=59), and mixed under conditionsof a kneading temperature of 210° C., an extrusion speed of 2.0 kg/hr,and a screw rotation speed of 200 rpm. The thus obtained modifier waspelletized by a pelletizer to obtain pellet shape of the modifier.

Second polyolefin resin: polypropylene resin, homopolymer, manufacturedby Japan Polypropylene Corporation, product name “NOVATEC MA1B”,weight-average molecular weight 312,000, melting point 165° C.

<2> Production of Molded Bodies of Examples 1 to 3

A molded body containing 90% by mass of a first polyolefin and 10% bymass of a modifier per 100% of its total mass (Example 1), a molded bodycontaining 80% by mass of a first polyolefin and 20% by mass of amodifier per 100% of its total mass (Example 2), and a molded bodycontaining 60% by mass of a first polyolefin and 40% by mass of amodifier per 100% of its total mass (Example 3) were each produced bythe following procedure.

The pellets of the modifier obtained in the above [1](2) and pellets ofthe following first polyolefin resin were dry-blended to obtain a moldedbody raw material. The obtained molded body raw material was fed into ahopper of an injection molding machine (manufactured by NISSEI PLASTICINDUSTRIAL CO., LTD., 40-ton injection molding machine) andinjection-molded under injection conditions of a set temperature of 210°C. and a mold temperature of 60° C. to obtain test specimens formeasuring physical properties.

First polyolefin resin (1): block copolymerized polyolefin resin havingan ethylene block as a dispersed phase, manufactured by SunAllomer Ltd.,product name “YS559N”, melting point 165° C.

<3> Production of Molded Bodies of Examples 4 to 6

A molded body containing 80% by mass of a first polyolefin and 20% bymass of a modifier per 100% of its total mass (Example 4), a molded bodycontaining 60% by mass of a first polyolefin and 40% by mass of amodifier per 100% of its total mass (Example 5), and a molded bodycontaining 40% by mass of a first polyolefin and 60% by mass of amodifier per 100% of its total mass (Example 6) were each produced bythe following procedure.

The modifier obtained in the above [1](2) and pellets of the followingfirst polyolefin resin were dry-blended to obtain a molded body rawmaterial. The obtained molded body raw material was fed into a hopper ofan injection molding machine (manufactured by NISSEI PLASTIC INDUSTRIALCO., LTD., 40-ton injection molding machine) and injection-molded underinjection conditions of a set temperature of 210° C. and a moldtemperature of 60° C. to obtain test specimens for measuring physicalproperties.

First polyolefin resin (2): Block copolymerized polyolefin resin havingan ethylene block as a dispersed phase, manufactured by SK Chemical Co.,Ltd., product name “BH3820”

<4> Production of Molded Bodies of Comparative Examples

(1) Production of Molded Body of Comparative Example 1

The following polyolefin resin (which was the same as the firstpolyolefin resin (1) used for the molded bodies of Examples 1 to 3) wasfed into a hopper of an injection molding machine (manufactured byNISSEI PLASTIC INDUSTRIAL CO., LTD., 40-ton injection molding machine)and injection-molded under injection conditions of a set temperature of210° C. and a mold temperature of 60° C. to obtain test specimens formeasuring physical properties.

Polyolefin resin (1): Block copolymerized polyolefin resin having anethylene block as a dispersed phase, manufactured by SunAllomer Ltd.,product name “YS559N”, melting point 165° C.

(2) Production of Molded Bodies of Comparative Examples 2 and 3

Pellets of the following impact resistance-imparting agentconventionally used to impart impact resistance and pellets of thefollowing polyolefin resin were dry-blended to obtain a molded body rawmaterial, and the molded body raw material was fed into a hopper of aninjection molding machine (manufactured by NISSEI PLASTIC INDUSTRIALCO., LTD., 40-ton injection molding machine) and injection-molded underinjection conditions of a set temperature of 210° C. and a moldtemperature of 60° C. to obtain test specimens for measuring physicalproperties.

Polyolefin resin (1): Block copolymerized polyolefin resin having anethylene block as a dispersed phase, manufactured by SunAllomer Ltd.,product name “YS559N”, melting point 165° C.

Impact resistance-imparting agent: manufactured by Mitsui Chemicals,Inc., product name “TAFMER DF810”

[2] Evaluations of Molded Bodies for Evaluation

(1) Measurement of Charpy Impact Strength

Measurement of Charpy impact strength was performed in accordance withJIS K 7111-1 using each of the specimens for evaluation of Examples 1 to6 and Comparative Examples 1 to 3 obtained in the above [1]. The resultsof the measurement are shown in Table 1 and Table 2. It is to be notedthat in the measurement of Charpy impact strength, impact strength wasmeasured at a temperature of 23° C. by an edgewise test method using aspecimen having a notch (type A).

(2) Observation of Morphology

A sample cut out from each of the test specimens of Examples 1 to 6 andComparative Examples 1 to 3 that had been subjected to the measurementof Charpy impact strength described above in (1) was embedded in aresin. Then, the sample was trimmed and cut in a cross section using anultramicrotome with a diamond knife and subjected to steam dyeing with ametal oxide. An ultrathin section sample was taken from the obtainedcross section after dyeing and observed with a transmission electronmicroscope (TEM, manufactured by Hitachi High-Technologies Corporation,Model “HT7700”) to observe a phase structure. The results of theobservation are shown in Table 1 and Table 2.

It is to be noted that an image obtained from the sample of Example 3 isshown in FIG. 2. As shown in FIG. 2, a continuous phase (A) containingthe first polyolefin resin and the second polyolefin resin, a dispersedphase (B) dispersed in the continuous phase (A) and containing thepolyamide resin, and the modified elastomer, a continuous phase (B₁)containing the polyamide resin, a fine dispersed phase (B₂) dispersed inthe continuous phase (B₁) and containing the modified elastomer, and anaggregate phase (D) in which an ethylene block of the first polyolefinresin is aggregated at the interface between the continuous phase (A)and the dispersed phase (B) were observed.

It is to be noted that the aggregate phase (D) contains not only theethylene block of the first polyolefin resin but also the modifiedelastomer.

(3) Measurement of Flexural Modulus

Measurement of flexural modulus was performed in accordance with JIS K7171 using the test specimens for evaluation of Examples 1 to 6 andComparative Examples 1 to 3 obtained in the above [1]. The results ofthe measurement are shown in Table 1 and Table 2. It is to be noted thatthe measurement of flexural modulus was performed by applying a load ata speed of 2 mm/min from an action point (curvature radius: 5 mm)located in the middle of the two points while supporting each of thetest specimens at two points (curvature radius: 5 mm) whose distance (L)is 64 mm.

A graph of the correlation between the Charpy impact strength and theflexural modulus is shown in FIG. 1.

TABLE 1 Examples Comparative Examples 1 2 3 1 2 3 First polyolefin (1)PP (block) 90 80 60 100 90 80 modifier Polyamide PA11 2.5 5 10 ModifiedMaleic 2 4 8 elastomer anhydride- modified EBR Second PP (homo) 5.5 1122 polyolefin Total of polyolefins 95.5 91 82 100 90 80 Conventionalimpact resistance- — — 10 20 imparting agent Phase Continuous phase (A)· Present Absent structure Dispersed phase (B) Continuous phase (B₁) ·Present Absent Fine dispersed phase (B₂) Interfacial aggregation ofPresent Absent EPR Charpy impact strength (kJ/m²) 23 39 53 12 13 21Flexural modulus (MPa) 1006 929 864 1100 938 809

TABLE 2 Examples 4 5 6 First polyolefin (2) PP (block) 80 60 40 modifierPolyamide PA11 5 10 15 Modified elastomer Maleic anhydride- 4 8 12modified EBR Second polyolefin PP (homo) 11 22 33 Total of polyolefins91 82 73 Phase Continuous phase (A) · Dispersed Present structure phase(B) Continuous phase (B₁) · Fine dispersed Present phase (B₂)Interfacial aggregation of EPR Present Charpy impact strength (kJ/m²) 5357 60 Flexural modulus (MPa) 845 830 810

[3] Effect

As can be seen from the results shown in Tables 1 and 2 and FIG. 1, when10% by mass of the conventionally-used impact resistance-imparting agentwas added (Comparative Example 2) to improve the impact resistance ofthe first polyolefin (Comparative Example 1), the Charpy impact strengthwas improved by 8.3%, whereas the Charpy impact strength of the moldedbody obtained using the modifier containing 10% by mass of the modifier(Example 1) was improved by 91.6%. This reveals that even when theamount of the modifier added is small, addition of the modifier issignificantly effective at imparting impact resistance. In addition,when 10% by mass of the conventionally-used impact resistance-impartingagent was added (Comparative Example 1), the flexural modulus wasreduced by 15.6%, whereas a reduction in the flexural modulus of themolded body obtained using the modifier containing 10% by mass of themodifier (Example 1) was suppressed to 8.5%. This reveals that areduction in rigidity can be extremely suppressed while significantlyhigh impact resistance is achieved. This tendency was consistentlyobserved in all the Examples 1 to 3. Further, the tendency wasconsistently observed also in all the Examples 4 to 6. This reveals thatthe effect can be exhibited irrespective of the type of the firstpolyolefin.

Further, as can be seen from the result shown in FIG. 2, a continuousphase (A′) and a dispersed phase (B) are formed in the molded bodyobtained using the modifier. Further, it can be seen that a finedispersed phase (B₂) is formed in the dispersed phase (B). In addition,it can be seen that when a block copolymerized polyolefin resin havingan ethylene block as a dispersed phase is used as the first polyolefinresin, at least part of the ethylene block (EPR) is aggregated at theinterface between the continuous phase (A) and the dispersed phase (B).It is considered that such aggregation results in more excellent impactresistance.

It is to be noted that the present invention is not limited to thespecific examples described above, and various modifications may be madeto the examples within the scope of the present invention depending onthe purpose or intended use.

More specifically, for example, in the above examples, molded bodieswere obtained by molding molded body raw materials obtained bydry-blending pellets of the modifier and pellets of the first polyolefinresin. However, pellets obtained by melt-kneading pellets of themodifier and pellets of the first polyolefin resin may, of course, beused as a molded body raw material.

The above-described examples are for illustrative purposes only, andshall not be construed as limiting the present invention. Although thepresent invention has been described with reference to exemplaryembodiments, it is understood that the words used in the description anddrawings of the present invention are explanatory and illustrativerather than restrictive. As described in detail herein, modificationsmay be made to the embodiments within the scope of the appended claimswithout departing from the scope and spirit of the present invention.Although the present invention has been described in detail withreference to particular structures, materials, and examples, the presentinvention is not intended to be limited to the particulars disclosedherein, rather the present invention extends to all thefunctionally-equivalent structures, methods, and uses within the scopeof the appended claims.

1. A modifier that can be added to a first polyolefin resin to obtain amolded body having improved impact resistance, the modifier comprising:a continuous phase (A) containing a second polyolefin resin; and adispersed phase (B) dispersed in the continuous phase (A) and containinga polyamide resin and a modified elastomer, wherein the dispersed phase(B) is composed of a melt-kneaded product of the polyamide resin and themodified elastomer having a reactive group that reacts with thepolyamide resin, and wherein when a total of the continuous phase (A)and the dispersed phase (B) is 100% by mass, a content of the dispersedphase (B) is 80% by mass or less.
 2. The modifier according to claim 1,wherein the modified elastomer is an olefin-based thermoplasticelastomer having, as its skeleton, a copolymer of ethylene or propyleneand an α-olefin having 3 to 8 carbon atoms, or a styrene-basedthermoplastic elastomer having a styrene skeleton.
 3. The modifieraccording to claim 1, wherein when a total of the polyamide resin andthe modified elastomer is 100% by mass, a content of the polyamide resinis 10% by mass or more but 80% by mass or less.
 4. The modifieraccording to claim 1, wherein the dispersed phase (B) has a continuousphase (B₁) containing the polyamide resin and a fine dispersed phase(B₂) dispersed in the continuous phase (B₁) and containing the modifiedelastomer.
 5. The modifier according to claim 1, wherein the firstpolyolefin resin is a block copolymerized polyolefin resin having anethylene block as a dispersed phase.
 6. A method for using the modifieraccording to claim 1, comprising mixing 0.5 parts by mass or more but 70parts by mass or less of the modifier per 100 parts by mass of the firstpolyolefin resin.
 7. A method for producing the modifier according toclaim 1, comprising a melt-kneading step in which the second polyolefinresin and a melt-kneaded product of the polyamide resin and the modifiedelastomer are melt-kneaded.
 8. A carrier for additives for use in addingan additive to a first polyolefin resin, comprising: a continuous phase(A) containing a second polyolefin resin; and a dispersed phase (B)dispersed in the continuous phase (A) and containing a polyamide resinand a modified elastomer, wherein the dispersed phase (B) is composed ofa melt-kneaded product of the polyamide resin and the modified elastomerhaving a reactive group that reacts with the polyamide resin, andwherein when a total of the continuous phase (A) and the dispersed phase(B) is 100% by mass, a content of the dispersed phase (B) is 80% by massor less.
 9. The carrier for additives according to claim 8, wherein theadditive is at least one of a flame retardant, a flame retardant aid, afiller, a colorant, an antimicrobial agent, an antistatic agent, and afoaming agent.